1. Field of the Invention
This invention relates to pump engineering, in particular to well pump units for studying, repairing, testing and developing wells.
2. Description of the Related Art
A well jet device is known, which comprises, all being installed on a pipe string upwards: a packer provided with a central channel, and a jet pump which body is provided with an active nozzle and a mixing chamber with a diffuser as well as a channel for supplying a working medium and a channel for supplying a medium pumped out of a well, a pass being made in the jet pump body with the possibility of installing replaceable functional inserts and a sealing assembly (see: RU Patent No. 2176336, PO4P 5/02, 27.11.2001).
The known well jet device enables to treat a formation below the jet pump level in a well, including treatment with creation a pressure differential between pressures above and below the sealing unit. However, the capacity of the known well jet device is not used in full, since a big time is required for replacing inserts, and such time is often greater than a time of reaction between an acid solution and minerals of a producing formation.
The closest to this invention as to its technical essence and achieved result is a well jet device for logging horizontal wells, which comprises, all being arranged on a flexible smooth pipe upwards, a packer provided with a central channel, and a jet pump which body is provided with a nozzle and a mixing chamber with a diffuser, the diffuser outlet being connected to the inner cavity of the flexible smooth pipe via a channel for removing a medium mixture, as made in the jet pump body, the inlet of the jet pump nozzle being connected to the annular space around the flexible smooth pipe, and the channel for supplying a medium pumped out of a well being connected to the inner cavity of the flexible smooth pipe via an upper and a lower windows made in the jet pump body, and a check valve being arranged in the channel for supplying a pumped-out medium on its inlet at the lower window, a multiple-measurement instrument being arranged on the lower end of the flexible smooth pipe, a sealing element shaped as a profiled ring being movably arranged on the flexible smooth pipe below the packer, and openings, which communicate the inner cavity of the flexible smooth pipe with the annular space below the packer, being made in the wall of the flexible smooth pipe above the multiple-measurement instrument (see: RU Patent No. 2324079, PO4P 5/54, 10.05.2008).
This well jet device enables to study horizontal wells and treat producing formations in them. However, an installed switch for working medium flows narrows the capacity of the device in studying productivity of a formation during treating it.